Brake mechanism



June 29, 1943. w. A. EATON `BRAKE MECHANISM Fiied Jan. 18, 1940 s sheets-sheet 1 f N@ 414// si K mm. D@ QN wb'gredAaou.

June 29,4 1943. w. A. EATON 2,323,207

BRAKE MECHANISM Filed Jan. 18, 1940 3 sheets-sheet z Q N" Q @3Q Wcmnfwm y' June 29, 1943. w. A. EATON BRAKE MECHANISM Filed Jan. 18, 1940 3 Sheets-Sheet 3 Patented June 29, 1943 Y azazazor l BMKEMECHANISM Y y '1 Wili'red Eaton,'Pittsburgh, Pa., assignor to vBendix-Westingliouse Automotive Air `Brake Company; Pittsburgh, Pa.,'a corporation of J Delaware: Y

Yllmilieauim:tammy 1s, 1940, seria'No. 314,538'

This invention relates to vehiclev braking sys' temsl and more particularly to a construction providing for the coordination of vehicle brake and clutch actuatingmeans. I

Y One of the objects of the present invention is.;4 tofprovide a novel arrangement 'forautomatically maintaining the brakes of` a vehicle applied under certain conditions ofoperation', thecon# structionbeing such that the brakeslmay be kept in applied position without the `necessity of the operator maintaining his foot'upon `the brake pedal. Such. a construction greatly facilitates the operation and control of. motor vehicles under crowded traillc conditions 'and avoidsv any. tendency of the vehicle tov roll down hill alteritl stop kand during the time when :the operator changes his foot from the brake pedal to theaccelerator pedal when proceeding forwardly after such stop. Another-object is to provide a Vconstruction 'of the above character wherein the vehicle braking system will be automatically maintained in applied position as soon as; the vehicle has been brought to rest by the manipulation ofthe usual brake pedal, such an arrangement permitting the operator to thereafter Vremove his foot from such pedal. i

Still another object resides in the coordination of thefvehicle clutch and brake systemsso that,

`when the motion ofthe vehicle isarrested and the clutch is disengaged, the braking system will be automatically maintained in applied position. A further object comprehends a novel vehicle.

control system wherein the vehicle brakes rwill automatically be /held i applied after fthe vehicle ,z

hasbeen stopped, and will not ,be .released until the 'operator shifts the transmission Tinto gear to move the vehicle fromres't. f

' A still further object is to provide a novel conf 4:0`

trolling mechanism of the above character which will be especially adaptable-for motor vehicles -equipped with fluidpressure brakingsystems.

Other objects and novel features of the invention will appear more'fully hereinafter from the following detailed descriptionf` whenr` taken in connection with the accompanying" drawings, wherein three embodiments of the inventionfare illustrated. Itis to be expressly understood, however, that theV drawings are employed for lpurposes of illustration only and are notdesignedas a definition of the limits of thej-invention.' reference being had for` this purpose to the appended claims.

In the drawings, wherein similar reference .and accelerates the engine in the usual'manner 'theother in' the casing I8V in order'tointerconcharacters refer to similar parts throughoutV the several views: 'f

Fig. -1 isa diagrammatic view, partly in section, of a vehicle controllingk mechanism "constructed inv accordancewith 4the present inventio'; i

Fig. 2 is a ldiagraminatic view, partlyinsection, of a modiiledjform of-theinve'ntion, and- Flg. 3 is a diagrmm'atic viewgfpartly in ysec-jv tion, 'of still another modication. I j' Referring more particularly to'Fig; 1,79'. vehicle controlling `mechanism constructed in accordance with the principles vof the presentinv'ention' is, illustrated'therein iny combination with a motor vehicle having an enginel;v a'brakf ing system 5 and Aa clutch system 6.' Preferably, the brake and clutch systems are'controlled by fluid actuators 1 and frespectively, a source of compressed air79 being provided for energizing the actuators. While the useofv compressed airy for actuatingthe clutch and brake systems isillustrated in the drawingsfand will be referred tol 'inthe following description, itv is to be understood' that anylsuitable source of fluid power 'maybe employed, such as a liquid under .pressureorfth vacuum obtainable from the Aintake manifold y of the engine.

In order to control communication between;l y thek brake actuator 1 andthe source -or reservoir 9; "these two `devices( areconnected by conduits "i0, Ii and i2," asu'itable manually-operable controlling valve I3 forming lthe connection between conduits Ii'and I2: The valve mechanism i 3 may be constructed inany suitable manner but is preferably constitutedlas disclosed `inthe patent to William J. Andres and `Roy S. Sanford, No. 2,133,275, grantedOctober 18,1938,

for Control "-mechanism. interposed :between 'conduits i0 and il is adoublecheckvalve Il in order tol permit flow of fluidfpressure to the conduit .l0 from either conduitil ora conduit i5, the latterbeing provided 'ffor a' purposewhich -will appear more fully hereinafter:y As shown,

the check valve-I4 includesv a casingilhousing a valve element llmovable to one extremity 'or nect conduits-i0 and llor conduits-Inland I5. Means 'arealso provided for controlling the lclutch-engaging anddisengaging movements of the clutch actuator 8 and preferably such means are so constructedvl that the clutchd's disengaged when the engine" idling` and ispermitted'to engage when the speedof the-'engine is gradually increased.V lAs shown, such means include acen-v trifugally-controlled valvular mechanism II valvular mechanism I5 operates in such a man# neras to exhaust fluid from the clutch actuator i through conduit 25, valvular mechanism I3 lprovides a supplemental means for applying the Fig. 1, through the action of the centrifgallyoperable members 25. Thus, the intake valve head 31 will be closed by means of spring 4I and member 40 will be moved away from the exhaust valve head 38 in order to gradually connect conduit with the atmospheric exhaust conduit 2| through member 40 and ports 39. Thus, the vehicle vclutchmay be smoothly engaged through the control ofthe engine speed.

Th'e present invention, as illustrated in Fig. 1,

brakes under certain conditions of'vehicle operation and independently of the released posiand an exhaust'connection 2l, and the construc-` tion is such that the fluid pressure is graduallyN exhausted, thus permitting the vehicle clutch to be smoothly engaged through the action of the usual clutch return springs associated therewith.

More particularly, the centrifugally-operated vs1vu1ar mechanism ls includes a shaft n drivably connected at one end with the engine through a beitand pulley drive v,23, the other end'of the shaft` having `a rotor 24 secured thereto and pxovid'edwith a plurality of centrifugally-actuated levers, one of which is shown at 25. These vlatter levers are adapted to cooperate through an arm 24 with a bearing 21 which is capable of a limited sliding `movement' with respect to the rotor. The bearing 21V is adapted topilot at ,one end a valve-actuating member 2 8,-and the latter is maintainedlna non-rotatable condition asby4 means of an extension 23 adapted `to. embrace a stud 3|! `carried bya casing 3| of the valvular mechanism I8. From this construction, it will be readily perceived that, as the speed of 'rotor 24 tion ofthe brakeA valve I3. Preferably, such independentbrake-applying and releasing means is effective to apply the brakes when the motion of the vehicle has been arrested and the clutch isdisengagedi it being understood that the words increases, centrifugal force will yeffect a movement of levers 25 about their pivotal yrnountings in order to cause levers 25 to move bearing 21 and valveactuating member 28 to the left, as viewed in Fig. l. ,The latter member isnormally urged toward the right, as viewed in this figure, through a'spring 32 confined between a portion of the casing 3| and a diaphragme secured vto member 2l as bymeans of elements 34 and 35.

'I'he valvular mechanism Il, inv addition to the "'centrifugally-operated actuating device heretohead, when opened, serving to connect conduits Il and` 20, and the exhaust. valve head ,38, when opened, serving to connectconduits l2li and 2I. ThisV latter connection includes a plurality of ports 39 positioned inthe member 23'and also includes a member 40 which` is hollowV and 'is adapted to form at'its right hand extremity` a seat for the exhaust valve head 33. The valve 3B has motion'of the vehicle as used above and hereinafter refer to movement of the Vehicle along its path of travel from one point to another. With such an arrangement, control ofthe vehicle is greatly simplified since, l`under lthe conditions above specified, the vehicle' brakes will be applied and the operator will be relieved ,of the necessity of keeping his foot upon the pedal of the 'brake valve I3. Such a construction'is especially desirablewfor preventing 'the v,vehicle from-rolling backwards on a down grade when itis desired to either arrest the motion of the vehicle because of trame, conditionsor move rthe 'vehicle forwardlyinflrst gear. t 'v Y In 'orderto provide the aforementioned auxiliary or supplementarybrake-applying means,` a valvularmechariism 42 isrin'terpcsed between con duit Ivanfdconduit I2 and, when opened to connect these`conduits`,vs erves to conduct fluid pressure from the-'reservoir sito the brake chamber# by way o fdouble check valve I4 and conduit I0. The valve 42 is soV constructed as vto close, the connection between conduits -I2 Iand I5 and con'- nect the latter to an atmospheric connection 43 in order to exhaust the brake chamber 1 under associated therewith a spring 4I which con stantlytendsto urgethe intake valve head towards closed position.. Y l

Preferably, the partsV of thecentrifugallyoperated valvular mechanism; Il are so initially ad- Justed that, with the engine idling, the spring 32 serves to move `the valve-actuatingrmember 28 to the right in orderV to effect contact between member '4l and exhaust valve head 3l and move the intakevalve 31 off its seat. Under these conditions, fluidpressure will be conducted from con- `duit I3 to conduit 20, and as heretoforefdescribed,

theA clutch actuator will be energized in'order'` to -eect disengagement lof ythevehicle clutch. When engagement of the clutch is desired, the engine y Aspeed is increased y and the valve-actuating member 23 willbe moved to thel left, as viewed .in

`with seats 1 48 and 49;

certain conditions of operation which willappear hereinafter. f A

' Preferably, the valve 42 may take the form of any suitable type of electromagnetically-con trolled valvular mechanism. lAs shown, the valve includes a casing44 having a valve 45'therein, the latter being provided'with an exhaust head 45 and an. intake. head 41 respectively cooperable. A spring v5Il normally serves to Amaintain'the valve 45,in lthe position yshown where the intake valve head-41 is closed, while theexhaust 'valve head .461s opened.- Under these conditions, conduit I5 Iis carried to the atmospheric connectionf 43 while zcommunication betweenconduits I2 and I5 isinterrupted. `The valve/45 is moved to open position by an electromagnetic. solenoid-II, the ,latter including a coil 52 having terminalsl 53 Vand 54, and surrounding an element 55 secured -to an armature 5B.v vThe construction iscsilchl that, upon energization of thevehicle but'also dependent upon energization of the` 4vehicle 'clutch actuator. As shown', a

switch 51` responsive 'to' vehicle speed'v and `a switch 4 |53 responsive to energization of the clutch actuator are arranged in series circuit with the coil $2 and a source of energy such as a battery i3. Such circuit includes connections G3 and il, connecting one side o! the battery 53 with a terminal 42 of switch 5I. The latter switch is also provided with a terminal $3 electrically "connected to terminal 54 of coil 52 vby a wire 34. the other terminal B3 of coil 52 having a wire 3l connected thereto which is also connected to the switch I1. As shown,'switch I1 comprises a pair of spring contacts 34 and 31, the latter being connected to the other terminal of battery Il as by Ameans of wire Il.

Normally, when the motion of the vehicle is arrested, spring contacts 64 and 61 are closed through the action ofa speed-responsive governor 49 which may be drivably connected through any suitable means to anydriven part of the vehicle, the motion oi which is arrested when the motion `of the vehicle' is stopped,

such as, for exampleythe propeller'shaft, not

The switch mechanism il, whichV as above indicated, is controlled by energization oiA the clutch actuator, comprises upper and lower casing sections 13 and 14 conilning 'a pressureresponsive element, such as a diaphragm 1l, therebetween. As shown, the upper casing section 13 is composed of insulating material and is formed with a downwardly-depending skirt4 14 for receiving and guiding a contact member 11 resting upon the'diaphragm 15. The upper portion of the contact member 11 is normally spaced from a contact 13 electricallyconnected with terminal 43 and is maintained in this position as by means of a spring 1l. `The upper portion of spring 1l is in constant engagement with a conductor 84 which is electrically connected with terminal 32, it beingapparent from this construction that, when contact member 11 engages contact 13, an electrical connection willbe made from terminal 32 to terminal 43 through conductor 8l, spring 13, contact member 11 and contact 13. In the position.4 shown in Fig. 1, however, there is no electrical connection between the terminals -42 `and 43 by reason oi' the separationof contacts 11 and 14.

In order to actuate the switch Il inaccordance with the energization of the clutch actuator I, space or chamber'll beneath diaphragm 15, and formed by theA lower casing section 14, is connected with conduit 20 as by means ofa conduit l2. Thus, upon energi'zation of the clutch actuator 8 vandrincrease in pressure in conduits contact 11 will be moved upwardly, as viewed inFig. 1, in order tocomplete the connection between terminals 62 and 63. Preferably, the tension of spring 13 is such that a substantial pressure will be required in chamber 4| before the aforementioned completion of the circuit between terminals and 63 is effected. This pressure is selected to be oi'such a value that the clutch actuator twill be Amoved to a position to eiect complete disengagement of the vehicle clutch before contacts 11 and 1l are engaged. Thisl insures disengagement of the stood that, as the pressure within chamber 3| is relieved in order to permit reengagement of the vehicle clutch, contacts 11 and 13 will be separated prior to engagement of the clutch, thus enabling actuation ofthe auxiliary valve 42-to release the brakes prior to kclutch engagement. For the purposeof Aadjusting the closingl and opening action ofcontacts 11 and 13,it is to be pointed out that` the casing vsections 13 and 14 are adjustably threaded. together and thus may be 'adjusted one with respect to the otherin order -to vary the ltension of spring 1.3 tolobtain the actionabove referred to. l.Should it be necessary, in order to properly adjust the tension of `spring 13,k to move the casingsection 13 outwardly with respect toca-sing section A14, it will be understood that. oneor more shlms may beinserted vabove the diaphragm engagement with the lower periphery of the upper hollow casing section 13 for the purpose oi' maintaining the marginal portion of lthe dia-v phragm in huid-tight engagement with the lower casing section 14.' f

With the construction heretofore provided, it will be' understood that, with the motion of the vehicle arrested, and the engin'e 4 idling. thesupplemental brake-applying valve 42. will be operated ln order to conduct duid pressurefrom the reservoir 3 to the brake actuator 1 through conduits` i2, |51 and Il. Assuming that lthe vehicle is arrested under these conditions, the operator may. sometimes-11nd it desirable to accelerate the engine. Such action. however, would cause engagement oi' the vehicle clutch through operation ot the vcentrli'ugally-controlled valve grade,` the operator, under these conditions,

would nd it necessary to reapply'the brakes through operation of the brake valve i3. In`

order to avoid this and enable the operator to accelerate the engine under the conditions above speciiied, a supplemental switch 33 is associated G0 20. and 82 and chamber 3l, diaphragm 1l and clutch before the auxiliary valve 42 opens to lwith the vehicle gear shift lever 84, such switch being arranged in parallel with the switch Il as by means ofconductors 35 and 86 respectively associated with conductors 34 and 6|'. ySwitch 33 vcomprises a pair 4oi' spring contacts 81 and Il respectively connected vto conductors 25 `and 34,'and such spring contacts are ynormally closed when thegear shift lever 34 isin neutral position. However, when the latter lever is moved neutral Vposition at this time, engagement offthe clutch through increase in speed of the engine 4-,will not fdeenergize coil I2 even though switch L5l is broken. Under these conditions.' coil 52 willl remain energized by reasons! the series circuit includingclosed switches 51 and 33.

A slightly modiiied form oi' the invention is disclosed in Fig. 2. In this embodiment, the arrangement is such that the .eflects of an yinstautaneous braking applicationby conducting full reservoir pressure to thek brake actuator 1 through the operation of valve 42 may be relieved for should the circuit of the valve 42 be closed and the valve thus energized prior to stopping of the vehicle. i While the centriiugally-operated device 99 is designed to close switch 91 when the motion of the vehicle has been completely arrested, it 'is possible that this switch may be closed when the vehicle speed has dropped to ya relatively low value, such as, iorexample, three toiive'miles per hour. Should-,closure of the switch 91 occurl at this speed, it kwill be` readily understood that, in the event of closure of switch 99, secured by energization of the clutch actuator 9, `coil 92 will be energized to open valve 42 and thus conduct full reservoirpressure to the brake chamber 1 by way oi'conduitsl! and I9, double check valve I4-and conduit I0. This would result in an instantaneous application o! the vehicle brakes and would cause discomfort to the passengers. i y i a In order to provide means for eilecting thel foregoing, the completion of the circuit to coil 92 is made dependent upon substantial deenegization of the brake actuators as caused by manipulation of brake valve I9. As shown, a pressure-responsive switch 90 is subjected to the pressure of the iluid in conduit II, through a conduit 9|and includes a pair ofv switch contact members 92'and 93 arranged in series between terminal 99 of switch 99 and terminal 94 of coi192 and the arrangement is such that, when conduit 9| is exhausted or the pressure dropped to a relatively low value, contacts 92and 99 will be closed.

Fig. 1. In the arrangement of Fig. 2, the switch 91 is also included in the series circuit including switches 99and 90 and, as in the case of Fig. 1, is

actuated by a centriiugally-responsive device.

which is connected to any suitable driven part of .the vehicle by the drive mechanism 10.

More particularly, theswitchf90 includes` a f casing having upper and lowersections 94 'and 99 respectively and having a pressure-responsive diaphragm 99 clamped therebetween. Switch housing member 91 is carried by the diaphragm 99 and supports the contact member 92, a spring 99 tending to maintain-thel switch i member` 92 in the' position illustrated. VThe diaphragm 99 is constantly urged in sucha direction as to tend to engage contacts 92 and 99 as by means of a spring 99. Lower casing-section 99' dennes a chamber |00 beneath diaphragm 99, and, when fluid pressure in this chamberis exhausted or reduced to a relatively low value, spring 99 isof Asuch a nature as to effect contact between inembers 92' and 99. The last named contact member vis carried by the lower casing section 99'inf-a suitable insulating bushing I0| and isvconnected to a terminal |02, the latterlbelng electrically connected-to terminal 99 of switch 99 by conductor |99. Contact member 92 is electrically connected to terminal |04 through spring 99, housing 91, a nut |09, spring 99 and upper casing section 90. The terminal |04 is connected with terminall 94 of switch 42 through a conductor Although, in this form of the invention, the clutch actuator 9 may be controlled by a centrifugally-operable valve mechanism vsuch asfthat similar to the valve I9 yof Fig. 1, a manually-operable controlling valvemay also be used if desired. As shown, Fig.' 2, a manually-operable controlling valve mechanism |01, similar inconstruction to the valve device |91, is interconnected between conduits I2 and 20 and maybe manually manipulated in a well known mannerv for controllingthe degree of lenergization of the clutch actuator 9. As in the case of Fig. 1,'switch device 99 is subjected to the pressure of the iiuid conducted to the clutch'actuator as by means of conduit 92 and this switch functions in precisely the same manner as the corresponding switch oi A further form ofthe invention is shown in Fig. 3 and includesabrake system 9 adapted to be controlled through operation oi.' the brake valve I9 and includesalso the clutch system 9, controlled `through manipulation of the clutch valve |01. 'I'he source of iiuid pressure ,9 is connected to the clutch and brake `valves by means of conduit I2 as in the two previously described forms oi theinvention.

In the modiiication of Fig. 3, the electrical means of Figs. l and2 for controllingthe application of the vehicle brakes independently ot operation'of the brake pedal I9 is dispensed with and a mechanically-operable arrangement is provided.` As shown, under certain conditions of operation, fluid pressure from conduit 29 issupplied to the brake actuator 1`through a conduit ||0, valve` device I, conduit ||2, valve device II9, conduit Il, double check valve I4 and conduit I9. Valve device I comprises'a casing ||4 having a valve III therein provided with intake and exhaust heads ||.9 and I |1 respectively.

Theintake valve head ||9 is adaptedto cooperate with a seat I|9 and, when closed, cuts oi! communicationbetween an intake chamber I|9 and an outlet chamber |2'9. Valve I9 is adapted to be actuated `byfmeans` of a valve actuating member |2| havingl a bore' |22 formed therein communicating with the atmosphere. Normally, the valve I|9 is urged to the right, as viewed in Fig. 3, through theaction of aspring |29 and is Voperated inthe opposite direction 'by sliding movement of the operating member |2| through the action of the centritugally-operable member 99 drivably connectedwith thegdriven part of the vehicle. VAtaero vehicle speed, the centrifugally-operable mechanism 99 moves the valveoperating member |2| to the left, as viewed in Fig. 3, the left hand extremity of which engages the exhaust valve head ||1 and moves the valve I I9 to such a position as to establish communioperable device 99 is so constituted thai; member 12 `will be moved. to. the' right, a.s viewed in Fig.y 3, thereby permitting spring |29 to close the intake valve II9 and open chamber |20 to the atmosphere through passage'I22. Thus, when the motion oi the vehicle is arrested, conduits |I9 and I|2' will be connected while the latter conduit will be connected to atmosphere when the vehicle is in motion.

Valve device I|9 interconnecting conduits I|2 and I9 is preferably constructed in accordance with the disclosure of the patent to Roy S. Santord, No. 2,128,165, granted August 23, 1938, for Vehicle control mechanism- Asshown, the valve device II9 includes a casing |24 having a valve |29 slida'bly arranged therein and normally urged to the position-shown as by .means-of a spring |29. 'Ihe casingV |24vis.Drovided with inlet and outlet ports |21 and |29, an exhaust port |29 being provided at the lower part ot thecasing. In the position illustrated, thev outlet port |29 communicates with the exhaust port |29 past a 'guide |99 provided with 'a plurality O1' flatsill.

Communication between the outlet port |29 and the inlet port is preventedby a valve part |92 will be noticed that the skirt |33 defines a rela, tively small area at the top of valve |25 which is subjected to the pressure of the fluid in the intake port |21 when the valve is in the position shown in Fig. 3. 'Ihe tension of spring |25 is adjusted in such a manner that the pressure in the intake |21 must rise to a value corresponding substantially to the pressure required to cause clutch-disengaging movement of the clutch actuator8 before valve |25 moves downwardly. When the pressure inthe intake port |21 reaches thisvalue, the valve |25 moves downwardly, as viewed in Fig.` 3, and, as soon as the skirt 133 leaves the seat |34, it will be understood that the pressure will act upon a substantially enlarged portion of the valve |25, namely the valve part |32. When this occurs, -the valve |25 will be moved downwardly with a snap action to ya point where ports |21 and |28-are in open communication and the exhaust port |29 is closed by 'engagement of a skirt |35 with an element |36. Fluid pressure from the conduit 2 may ,then beconducted through the valve device H3 dto thebrake actuator 1 to apply the vehicle controlled solely by reducing the pressure of the filuidin the clutch actuator 8 through manipula- Vfilon of the clutch valve |01. When this occurs,

valve device ||3 is of such nature as to rmain open and maintain communication between conduits I5 and ||2 until the pressure of the fluid in the clutch actuator and conduit 20 is reduced substantially to a value where the clutch is about to engage. When this pressure is released, spring |26;y of valvedevice ||3 will snap valve member |25;downwardly to close communication between ports |21A and |28 and establish communication between the latter port and the exhaust port |29. Conduit |5 and brake actuator 1 will thus be exhausted to atmosphere and the brakes released prior to actual engagementv` of the clutch. Subsequent manipulation of the clutch valve |01 will serve to further release the pressure in the clutch actuator 8 in order to permit the vehicle clutch to be smoothly engaged under the actionk of the usual return springs associated therewith.

In operation of that form of the invention disclosed in Fig. 1, it will be understood that the brake system -5 may be controlledk in the usual mannerby means ofthe brake valve I3, operation of which serves to connect reservoir 9 to brake actuator 1 through conduits yl2 and double check valve I4 and conduit |0. Normal vision of the switch .83, closed by moving the 83. When engine 4 is accelerated, it will berei called thatconduit leading to the clutch actuator 8 isv exhausted. and switch 58 is opened. When it is desired to move the vehicle forwardly in first gear, for example, it is only ynecessary to move the gear lever 54 to first-gear position.'

y This. -of course, permits switch 83 to be opened operation .of the clutch system 5 is controlled solely by operation of the centrifugal valve mechanism |8 through variations in the speed of the vehicle engine 4 as has been heretofore pointed `out in detail. In the event thatthe motion of the vehicle has been arrested and the speed of the engine 4 is reduced to normal idling, it will be apparent that switches 51 and 58. will beclosed avoid the disadvantageous results `which would,

brake actuator 1 with reservoir pressure through conduits I2 and I5, double check valve |4 and -conduit |0. Thus,l the brakes areautomatically held applied when the motion of the vehicle is arrested and the clutch is disengaged. The pro'- butthe coil 52 is still maintainedenergized asy by meansof closed switches 51 and 58. Upon acceleration of the engine with the transmission established in first gear ratio, the centrifugal valvular mechanism |8 willoperate toy gradually exhaust the fiuidin the ciutchactuator 8. The

pressure-responsive. switch 58 is so constructed.

however, as heretotorepointed out, that contacts 11 and 15 will be opened` prior to actual engagement of the clutch. Thus,the circuit to the coil 52 will be interrupted and the spring 50 acting upon the valve 45 ofl valve device 42 will close the intake valve head 41 and open the exhaust valve head 45. This action will vconnect conduit l|5 to the atmospheric connection 43 and thus the brake actuator 1 will be exhaustedthrough conduit I0, double check valveV I4 andconduit |5V to the atmosphere. Further increase in speed of the engine 4 willfserve to further decrease the f pressure of the fluid inl the clutch actuatorzl, thus permitting the vehicle clutch to be smoothly engaged under the action of the usual return springs associated therewith.

With reference to the operation of the4 moditlcation disclosedin Fig. 2, it will be recalledl that the circuit for energizing coil 52 in order to conn'ect the brake actuators 1 with the reservoir l is controlled by switches `5l, 58 and 3,0, all arranged inseries relation. In the event that the motion of the vehiclek has been arrested, switch 51 will be closed. Switch 55 will also be closed by reason o! the iluid pressure in conduit 20 and Y clutch actuator 8, admitted` to ,the latter by oper; ation of clutch valve |01 to disengagev the clutch'. Assuming that the operator has released pressure upon the brake valve kIl, no pressure will vbe present in chamber |00 beneath the diaphragm 95 of the valve device 90 and contacts 92and 88 will also be closed. Under these conditions, energization of coil' 52 will operate valvedevice'42 to connect conduits I2 and I5 and thus conduct iluid pressure to the vbrake actuators 1. In the, f

event, however, that switches 90 and 58 are closed and switch 51 closes at a. relatively low vehicle speed, as for example three to five miles per hour, it willbe understood that full reservoir pressure is applied to the brake actuator k1. In order vto accompany such action, the valve deviceis sol constructed that .it is only necessary for .the operator to exert' suiiicient pressure upon the pedal of the brake valve I3 to admita relatively slight pressureto the/brake conduit Hand tothe chamber |00. Forexample, the springl 83 may besoconstructed that a pressureof tenpou-nds per square inch vadmitted to the chamber |00 would cause disengagement of the contacts 52 and 83. The circuit to coil 52 would thus beimmediately interrupted, valve 4 5 wouldte'moved" to. exhaust position and the pressure inthe brake Y chamber' I reduced to an amount equal tothe slight pressure admitted to conduit by the above referred to operation oi' the brake valve I3. Thus, the disadvantageous results which would follow from full application of the vehicle brakes whilexthe vehicle is moving may bev readily con trolled by the brake valve II. c

In the operation of the form of the ,invention shown in Fig. 3, the brake and clutch actuators 1 and 8' respectively may be controlled during ordinary operation of the vehicle as in the modificatlon shown in Fig. 2. Assuming, however, that the motion of the vehicle is arrested and that clutch valve |01 is operated to effect disengagement of the ,vehicle clutch, iluid pressure from the clutch conduit 2|! will be conducted to the brake actuator v1`by way of conduit I||i,'valve device conduit ||2, valve device H3, conduit Il, double check valve I4 andfcon'duit I0. In the operation oi' valve device H3, it will be recalled that the valve |'thereof will not be moved to open position until conduit ||2is supplied with iluid pressure substantially equal to that required to'disengagethe clutch. When it is desired to move the vehicle forwardly in gear, it is only necessary to operate the clutch valve |01 to gradually exhaust the pressure in the clutch' actuator l. As soon as the pressure i-n conduit H2 reaches a value slightly above that at which the clutch begins to engage, valve |25y will 'be snapped to closed position through the action of spring |26; thereupon immediately connecting the brake chamber 1'to the atmospheric connection |29 oi valve device III throughy conduit l0, double check valve Hand conduit I5. 'I'hereafter, further operation of valve |01 will serve to further release the fluid pressure in clutch actuator l and permit the clutch to become engaged. There is thus provided by the present invention a series of novel arrangements'for controlling the action of a vehicle braking system in such a manarrested, the brakes kare automatically applied and it will not be necessary -for the operator `to maintain his foot on the brakejpedal. Such constructions,it will be readily appreciated, oier the advantages of simplified control and ease of manipulation of vehicles under crowded conditions ot trailic and especially when vehicles are required to be stopped on up grades.

While several embodiments of the invention have been disclosed herein anddescribed with considerable particularity, it isto be understood that modiilcations andchanges may be resorted to without' departing from the spirit of the invention, as well understood by those skilled in the l art. Reference will, therefore, be had to the appended claims for a' dennition of the limits of the invention.

What is claimed is: 4

l. In a motor 'vehicle' provided with a nuid pressure-braking system and a' clutch device, a source of'iluid pressure, a brake chamber, a iluid pressure-operated clutch motor, means including a valve forA connecting 'said source and chamber to apply thegbrake in service, means including a separate valve for connectingsaid source and motor to energize the latterto operate said clutch device, and means responsive respectively to energization o1' said motor and the stopping of said vehicle for, connecting said brake chamber and source. l

2. In a motor vehicle vprovided with a iluid braking system and a clutch device, a source of fluid pressure, ra brakechamber, a brake valve for supplying nuid pressure from-said source to ner that, when the motion of the vehiclehas been said chamber, and means operable to connect said source and brake chamber upon energization of said clutch device including a device responsive to the speed of the vehicle.

3. In a motor vehicle provided with a nuid braking system and a clutch device, means .for actuating said device, a source of iluid pressure, a brake chamber, s, brakevalve for supplying fluid pressure from rsaid source to said chamber, other means for supplying nuid pressure to said chamberfrom said source, a valve in said other means, and meansior opening said last named valve including means responsive .to the energizationy oi said ilrst named means and a device responsive to the speed of the vehicle.

4. In a motor vehicle provided with a nuid pressure braking system and a clutch device, a source of iluid pressure. a brake chamber, a i'iuid pressure-operated clutch motor, means including a valve for connecting saidsource and chamber to apply the brake in service, means including a separate valve for connecting said source and motor to energize the latter tooperate said clutch device, and other "means for connecting said source and chamber including controlling mechanism having a device responsive to the fluid pressure in said motor and another device responsive to the speed of the vehicle.

5. In a motor vehicle'having a iluid pressure braking system and a fluid pressure-operated clutch system, means to control the braking system to apply the brakes, mechanism to control the clutch system to operate the vehicle clutch, and means to control application of the brakes during operation of said mechanism,v said'last named means including" means responsive to the pressure in the clutch system and a device actuated to operative position by the stoppingoi the vehicle.k

6. In a motor vehicle having brakes and a clutch-controlling member, operator-controlled means for controlling applying and releasing `of the brakes, means for operating said member, and other means for controlling applying and releasing of said brakes dependent upon operation oi saiili second means and the stopping of said vehic e.

'7. In a motor vehicle provided with a iluid braking system and a clutch device, a source of iluid power, a b rake chamber, a valve for 'controlling communication between said source and chamber to cause application and release of the brakes, a connection between said chamber andv source, a valve in said connection, and means to control the last named valve including a. device responsive to energization of said clutch device and a mechanism responsive to the speed of the vehicle. y l' l 8. In a motor .vehicle having ybrakes and a clutch device, means for controlling applying and releasing the brakes,` other means for controlling applying and releasing the brakes, and means dependent upon operation ci said clutch device. and the stopping of the vehicle for controlling said other means.

' v 9. A mechanism of the class described comprising a brake-operating member, a clutchoperating member, operator-controlled means for controlling energization of said brake member, 'a fluid motor connected with said clutch member, means for controlling the energization of said motor, other means for controlling energizatlon of said brake member, and controlling means for said other means actuated when the vehicle stops and the motor is energized to a predetermined degree 10. In a motor vehicle having a fluid pressure braking system and a iluid pressure-.operated clutch device, a source of fluid power, valve means for controlling communication between said braking system and source, a valve device for connecting vsaid source and clutch device,

means separate from said valve means for con-V necting the braking system and source, a valve in said separate means, and means for opening the last named valve when the vehicle stops and the pressure or the duid supplied said clutch device reaches a predetermined value.

ll. In a motor vehicle having a fluid pressure` braking system and a `iluid pressure-operated clutch dev-ice, a source of iluid power, valve means for controlling communication between said braking system and source, a valve device for connecting said source and clutch device, means separate from said valve .means for connecting" the braking system and source, a valve in said separate means, electromagnetic means for opening said valve, and a .circuit for controlling thev electromagnetic means comprising a pair of switches arranged in series, one of said switches being controlled in accordance with the speed of the vehiclewhile the. other is controlled in accordance with the degree of energization of saidclutch device.J

l2. In a motor vehicle having an engine,

the brakes, separate operator-controlled means for eiIecting brake-releasing action oi' said auxiliary means, and means operable in response to brake-releasing action of said first .named means for controlling the auxiliary means for applying the brakes including a device responsive to vehicle speed.

14. A vehicle' brake system comprising operator-controlled means for controlling applying and releasing of the brakes, separate brakeapplying and releasing controllingmeans, means including adevice responsive to vehicle speed for operating said separate means inv response to release of said first means, and means controlled byfthe operator for rendering said separate means effective for releasing the brakes.

15.. In av motor vehicle having a fluid pressure braking system and a iluid pressure-operated clutch system, asource or iluid pressure, a conduit connecting said source and' braking system, a valve in said conduit. a second Iconduit connectingthe` source and clutch system, a valve' device in said second conduit, and meansy connecting said second conduit and the braking system combrakes, a clutch device and a gear shift member,

13. A vehicle brake system' comprising means under the control of the operator for `controlling -applying and releasing oi' the brakes. auxiliary means for controlling applying and releasingot prising a valve governed by vehicle speed and a second valve movable -to open position at a predetermined pressure and movable to closed position at a diierent predetermined pressure.'

16.' The combination ina motor vehicle having j.

an engine, brakes and operator controlled means for controlling applying` and releasing of the brakes, oi' other means for controlling-applyingand releasing of the brakes and means controlled by the speed of the engine andl by-the speed of the vehicle'for controlling the operation of saidv other means.

l'l. 'Ihe combination in a motor vehicle having an engine, brakes and operator controlled means for controlling applying and releasing oi' the brakes, ot other means for controlling applying and releasing of the brakes and means operative l when the vehicle and engine are stopped for rendering said other means eil'ective to' apply the brakes.

WIIFRED A. EATON. 

